/* * TI HECC (CAN) device driver * * This driver supports TI's HECC (High End CAN Controller module) and the * specs for the same is available at * * Copyright (C) 2009 Texas Instruments Incorporated - http://www.ti.com/ * Copyright (C) 2019 Jeroen Hofstee * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation version 2. * * This program is distributed as is WITHOUT ANY WARRANTY of any * kind, whether express or implied; without even the implied warranty * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DRV_NAME "ti_hecc" #define HECC_MODULE_VERSION "0.7" MODULE_VERSION(HECC_MODULE_VERSION); #define DRV_DESC "TI High End CAN Controller Driver " HECC_MODULE_VERSION /* TX / RX Mailbox Configuration */ #define HECC_MAX_MAILBOXES 32 /* hardware mailboxes - do not change */ #define MAX_TX_PRIO 0x3F /* hardware value - do not change */ /* Important Note: TX mailbox configuration * TX mailboxes should be restricted to the number of SKB buffers to avoid * maintaining SKB buffers separately. TX mailboxes should be a power of 2 * for the mailbox logic to work. Top mailbox numbers are reserved for RX * and lower mailboxes for TX. * * HECC_MAX_TX_MBOX HECC_MB_TX_SHIFT * 4 (default) 2 * 8 3 * 16 4 */ #define HECC_MB_TX_SHIFT 2 /* as per table above */ #define HECC_MAX_TX_MBOX BIT(HECC_MB_TX_SHIFT) #define HECC_TX_PRIO_SHIFT (HECC_MB_TX_SHIFT) #define HECC_TX_PRIO_MASK (MAX_TX_PRIO << HECC_MB_TX_SHIFT) #define HECC_TX_MB_MASK (HECC_MAX_TX_MBOX - 1) #define HECC_TX_MASK ((HECC_MAX_TX_MBOX - 1) | HECC_TX_PRIO_MASK) /* RX mailbox configuration * * The remaining mailboxes are used for reception and are delivered * based on their timestamp, to avoid a hardware race when CANME is * changed while CAN-bus traffic is being received. */ #define HECC_MAX_RX_MBOX (HECC_MAX_MAILBOXES - HECC_MAX_TX_MBOX) #define HECC_RX_FIRST_MBOX (HECC_MAX_MAILBOXES - 1) #define HECC_RX_LAST_MBOX (HECC_MAX_TX_MBOX) /* TI HECC module registers */ #define HECC_CANME 0x0 /* Mailbox enable */ #define HECC_CANMD 0x4 /* Mailbox direction */ #define HECC_CANTRS 0x8 /* Transmit request set */ #define HECC_CANTRR 0xC /* Transmit request */ #define HECC_CANTA 0x10 /* Transmission acknowledge */ #define HECC_CANAA 0x14 /* Abort acknowledge */ #define HECC_CANRMP 0x18 /* Receive message pending */ #define HECC_CANRML 0x1C /* Receive message lost */ #define HECC_CANRFP 0x20 /* Remote frame pending */ #define HECC_CANGAM 0x24 /* SECC only:Global acceptance mask */ #define HECC_CANMC 0x28 /* Master control */ #define HECC_CANBTC 0x2C /* Bit timing configuration */ #define HECC_CANES 0x30 /* Error and status */ #define HECC_CANTEC 0x34 /* Transmit error counter */ #define HECC_CANREC 0x38 /* Receive error counter */ #define HECC_CANGIF0 0x3C /* Global interrupt flag 0 */ #define HECC_CANGIM 0x40 /* Global interrupt mask */ #define HECC_CANGIF1 0x44 /* Global interrupt flag 1 */ #define HECC_CANMIM 0x48 /* Mailbox interrupt mask */ #define HECC_CANMIL 0x4C /* Mailbox interrupt level */ #define HECC_CANOPC 0x50 /* Overwrite protection control */ #define HECC_CANTIOC 0x54 /* Transmit I/O control */ #define HECC_CANRIOC 0x58 /* Receive I/O control */ #define HECC_CANLNT 0x5C /* HECC only: Local network time */ #define HECC_CANTOC 0x60 /* HECC only: Time-out control */ #define HECC_CANTOS 0x64 /* HECC only: Time-out status */ #define HECC_CANTIOCE 0x68 /* SCC only:Enhanced TX I/O control */ #define HECC_CANRIOCE 0x6C /* SCC only:Enhanced RX I/O control */ /* TI HECC RAM registers */ #define HECC_CANMOTS 0x80 /* Message object time stamp */ /* Mailbox registers */ #define HECC_CANMID 0x0 #define HECC_CANMCF 0x4 #define HECC_CANMDL 0x8 #define HECC_CANMDH 0xC #define HECC_SET_REG 0xFFFFFFFF #define HECC_CANID_MASK 0x3FF /* 18 bits mask for extended id's */ #define HECC_CCE_WAIT_COUNT 100 /* Wait for ~1 sec for CCE bit */ #define HECC_CANMC_SCM BIT(13) /* SCC compat mode */ #define HECC_CANMC_CCR BIT(12) /* Change config request */ #define HECC_CANMC_PDR BIT(11) /* Local Power down - for sleep mode */ #define HECC_CANMC_ABO BIT(7) /* Auto Bus On */ #define HECC_CANMC_STM BIT(6) /* Self test mode - loopback */ #define HECC_CANMC_SRES BIT(5) /* Software reset */ #define HECC_CANTIOC_EN BIT(3) /* Enable CAN TX I/O pin */ #define HECC_CANRIOC_EN BIT(3) /* Enable CAN RX I/O pin */ #define HECC_CANMID_IDE BIT(31) /* Extended frame format */ #define HECC_CANMID_AME BIT(30) /* Acceptance mask enable */ #define HECC_CANMID_AAM BIT(29) /* Auto answer mode */ #define HECC_CANES_FE BIT(24) /* form error */ #define HECC_CANES_BE BIT(23) /* bit error */ #define HECC_CANES_SA1 BIT(22) /* stuck at dominant error */ #define HECC_CANES_CRCE BIT(21) /* CRC error */ #define HECC_CANES_SE BIT(20) /* stuff bit error */ #define HECC_CANES_ACKE BIT(19) /* ack error */ #define HECC_CANES_BO BIT(18) /* Bus off status */ #define HECC_CANES_EP BIT(17) /* Error passive status */ #define HECC_CANES_EW BIT(16) /* Error warning status */ #define HECC_CANES_SMA BIT(5) /* suspend mode ack */ #define HECC_CANES_CCE BIT(4) /* Change config enabled */ #define HECC_CANES_PDA BIT(3) /* Power down mode ack */ #define HECC_CANBTC_SAM BIT(7) /* sample points */ #define HECC_BUS_ERROR (HECC_CANES_FE | HECC_CANES_BE |\ HECC_CANES_CRCE | HECC_CANES_SE |\ HECC_CANES_ACKE) #define HECC_CANES_FLAGS (HECC_BUS_ERROR | HECC_CANES_BO |\ HECC_CANES_EP | HECC_CANES_EW) #define HECC_CANMCF_RTR BIT(4) /* Remote transmit request */ #define HECC_CANGIF_MAIF BIT(17) /* Message alarm interrupt */ #define HECC_CANGIF_TCOIF BIT(16) /* Timer counter overflow int */ #define HECC_CANGIF_GMIF BIT(15) /* Global mailbox interrupt */ #define HECC_CANGIF_AAIF BIT(14) /* Abort ack interrupt */ #define HECC_CANGIF_WDIF BIT(13) /* Write denied interrupt */ #define HECC_CANGIF_WUIF BIT(12) /* Wake up interrupt */ #define HECC_CANGIF_RMLIF BIT(11) /* Receive message lost interrupt */ #define HECC_CANGIF_BOIF BIT(10) /* Bus off interrupt */ #define HECC_CANGIF_EPIF BIT(9) /* Error passive interrupt */ #define HECC_CANGIF_WLIF BIT(8) /* Warning level interrupt */ #define HECC_CANGIF_MBOX_MASK 0x1F /* Mailbox number mask */ #define HECC_CANGIM_I1EN BIT(1) /* Int line 1 enable */ #define HECC_CANGIM_I0EN BIT(0) /* Int line 0 enable */ #define HECC_CANGIM_DEF_MASK 0x700 /* only busoff/warning/passive */ #define HECC_CANGIM_SIL BIT(2) /* system interrupts to int line 1 */ /* CAN Bittiming constants as per HECC specs */ static const struct can_bittiming_const ti_hecc_bittiming_const = { .name = DRV_NAME, .tseg1_min = 1, .tseg1_max = 16, .tseg2_min = 1, .tseg2_max = 8, .sjw_max = 4, .brp_min = 1, .brp_max = 256, .brp_inc = 1, }; struct ti_hecc_priv { struct can_priv can; /* MUST be first member/field */ struct can_rx_offload offload; struct net_device *ndev; struct clk *clk; void __iomem *base; void __iomem *hecc_ram; void __iomem *mbx; bool use_hecc1int; spinlock_t mbx_lock; /* CANME register needs protection */ u32 tx_head; u32 tx_tail; struct regulator *reg_xceiver; }; static inline int get_tx_head_mb(struct ti_hecc_priv *priv) { return priv->tx_head & HECC_TX_MB_MASK; } static inline int get_tx_tail_mb(struct ti_hecc_priv *priv) { return priv->tx_tail & HECC_TX_MB_MASK; } static inline int get_tx_head_prio(struct ti_hecc_priv *priv) { return (priv->tx_head >> HECC_TX_PRIO_SHIFT) & MAX_TX_PRIO; } static inline void hecc_write_lam(struct ti_hecc_priv *priv, u32 mbxno, u32 val) { __raw_writel(val, priv->hecc_ram + mbxno * 4); } static inline u32 hecc_read_stamp(struct ti_hecc_priv *priv, u32 mbxno) { return __raw_readl(priv->hecc_ram + HECC_CANMOTS + mbxno * 4); } static inline void hecc_write_mbx(struct ti_hecc_priv *priv, u32 mbxno, u32 reg, u32 val) { __raw_writel(val, priv->mbx + mbxno * 0x10 + reg); } static inline u32 hecc_read_mbx(struct ti_hecc_priv *priv, u32 mbxno, u32 reg) { return __raw_readl(priv->mbx + mbxno * 0x10 + reg); } static inline void hecc_write(struct ti_hecc_priv *priv, u32 reg, u32 val) { __raw_writel(val, priv->base + reg); } static inline u32 hecc_read(struct ti_hecc_priv *priv, int reg) { return __raw_readl(priv->base + reg); } static inline void hecc_set_bit(struct ti_hecc_priv *priv, int reg, u32 bit_mask) { hecc_write(priv, reg, hecc_read(priv, reg) | bit_mask); } static inline void hecc_clear_bit(struct ti_hecc_priv *priv, int reg, u32 bit_mask) { hecc_write(priv, reg, hecc_read(priv, reg) & ~bit_mask); } static inline u32 hecc_get_bit(struct ti_hecc_priv *priv, int reg, u32 bit_mask) { return (hecc_read(priv, reg) & bit_mask) ? 1 : 0; } static int ti_hecc_set_btc(struct ti_hecc_priv *priv) { struct can_bittiming *bit_timing = &priv->can.bittiming; u32 can_btc; can_btc = (bit_timing->phase_seg2 - 1) & 0x7; can_btc |= ((bit_timing->phase_seg1 + bit_timing->prop_seg - 1) & 0xF) << 3; if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) { if (bit_timing->brp > 4) can_btc |= HECC_CANBTC_SAM; else netdev_warn(priv->ndev, "WARN: Triple sampling not set due to h/w limitations"); } can_btc |= ((bit_timing->sjw - 1) & 0x3) << 8; can_btc |= ((bit_timing->brp - 1) & 0xFF) << 16; /* ERM being set to 0 by default meaning resync at falling edge */ hecc_write(priv, HECC_CANBTC, can_btc); netdev_info(priv->ndev, "setting CANBTC=%#x\n", can_btc); return 0; } static int ti_hecc_transceiver_switch(const struct ti_hecc_priv *priv, int on) { if (!priv->reg_xceiver) return 0; if (on) return regulator_enable(priv->reg_xceiver); else return regulator_disable(priv->reg_xceiver); } static void ti_hecc_reset(struct net_device *ndev) { u32 cnt; struct ti_hecc_priv *priv = netdev_priv(ndev); netdev_dbg(ndev, "resetting hecc ...\n"); hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_SRES); /* Set change control request and wait till enabled */ hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_CCR); /* INFO: It has been observed that at times CCE bit may not be * set and hw seems to be ok even if this bit is not set so * timing out with a timing of 1ms to respect the specs */ cnt = HECC_CCE_WAIT_COUNT; while (!hecc_get_bit(priv, HECC_CANES, HECC_CANES_CCE) && cnt != 0) { --cnt; udelay(10); } /* Note: On HECC, BTC can be programmed only in initialization mode, so * it is expected that the can bittiming parameters are set via ip * utility before the device is opened */ ti_hecc_set_btc(priv); /* Clear CCR (and CANMC register) and wait for CCE = 0 enable */ hecc_write(priv, HECC_CANMC, 0); /* INFO: CAN net stack handles bus off and hence disabling auto-bus-on * hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_ABO); */ /* INFO: It has been observed that at times CCE bit may not be * set and hw seems to be ok even if this bit is not set so */ cnt = HECC_CCE_WAIT_COUNT; while (hecc_get_bit(priv, HECC_CANES, HECC_CANES_CCE) && cnt != 0) { --cnt; udelay(10); } /* Enable TX and RX I/O Control pins */ hecc_write(priv, HECC_CANTIOC, HECC_CANTIOC_EN); hecc_write(priv, HECC_CANRIOC, HECC_CANRIOC_EN); /* Clear registers for clean operation */ hecc_write(priv, HECC_CANTA, HECC_SET_REG); hecc_write(priv, HECC_CANRMP, HECC_SET_REG); hecc_write(priv, HECC_CANGIF0, HECC_SET_REG); hecc_write(priv, HECC_CANGIF1, HECC_SET_REG); hecc_write(priv, HECC_CANME, 0); hecc_write(priv, HECC_CANMD, 0); /* SCC compat mode NOT supported (and not needed too) */ hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_SCM); } static void ti_hecc_start(struct net_device *ndev) { struct ti_hecc_priv *priv = netdev_priv(ndev); u32 cnt, mbxno, mbx_mask; /* put HECC in initialization mode and set btc */ ti_hecc_reset(ndev); priv->tx_head = HECC_TX_MASK; priv->tx_tail = HECC_TX_MASK; /* Enable local and global acceptance mask registers */ hecc_write(priv, HECC_CANGAM, HECC_SET_REG); /* Prepare configured mailboxes to receive messages */ for (cnt = 0; cnt < HECC_MAX_RX_MBOX; cnt++) { mbxno = HECC_MAX_MAILBOXES - 1 - cnt; mbx_mask = BIT(mbxno); hecc_clear_bit(priv, HECC_CANME, mbx_mask); hecc_write_mbx(priv, mbxno, HECC_CANMID, HECC_CANMID_AME); hecc_write_lam(priv, mbxno, HECC_SET_REG); hecc_set_bit(priv, HECC_CANMD, mbx_mask); hecc_set_bit(priv, HECC_CANME, mbx_mask); hecc_set_bit(priv, HECC_CANMIM, mbx_mask); } /* Enable tx interrupts */ hecc_set_bit(priv, HECC_CANMIM, BIT(HECC_MAX_TX_MBOX) - 1); /* Prevent message over-write to create a rx fifo, but not for * the lowest priority mailbox, since that allows detecting * overflows instead of the hardware silently dropping the * messages. */ mbx_mask = ~BIT(HECC_RX_LAST_MBOX); hecc_write(priv, HECC_CANOPC, mbx_mask); /* Enable interrupts */ if (priv->use_hecc1int) { hecc_write(priv, HECC_CANMIL, HECC_SET_REG); hecc_write(priv, HECC_CANGIM, HECC_CANGIM_DEF_MASK | HECC_CANGIM_I1EN | HECC_CANGIM_SIL); } else { hecc_write(priv, HECC_CANMIL, 0); hecc_write(priv, HECC_CANGIM, HECC_CANGIM_DEF_MASK | HECC_CANGIM_I0EN); } priv->can.state = CAN_STATE_ERROR_ACTIVE; } static void ti_hecc_stop(struct net_device *ndev) { struct ti_hecc_priv *priv = netdev_priv(ndev); /* Disable the CPK; stop sending, erroring and acking */ hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_CCR); /* Disable interrupts and disable mailboxes */ hecc_write(priv, HECC_CANGIM, 0); hecc_write(priv, HECC_CANMIM, 0); hecc_write(priv, HECC_CANME, 0); priv->can.state = CAN_STATE_STOPPED; } static int ti_hecc_do_set_mode(struct net_device *ndev, enum can_mode mode) { int ret = 0; switch (mode) { case CAN_MODE_START: ti_hecc_start(ndev); netif_wake_queue(ndev); break; default: ret = -EOPNOTSUPP; break; } return ret; } static int ti_hecc_get_berr_counter(const struct net_device *ndev, struct can_berr_counter *bec) { struct ti_hecc_priv *priv = netdev_priv(ndev); bec->txerr = hecc_read(priv, HECC_CANTEC); bec->rxerr = hecc_read(priv, HECC_CANREC); return 0; } /* ti_hecc_xmit: HECC Transmit * * The transmit mailboxes start from 0 to HECC_MAX_TX_MBOX. In HECC the * priority of the mailbox for transmission is dependent upon priority setting * field in mailbox registers. The mailbox with highest value in priority field * is transmitted first. Only when two mailboxes have the same value in * priority field the highest numbered mailbox is transmitted first. * * To utilize the HECC priority feature as described above we start with the * highest numbered mailbox with highest priority level and move on to the next * mailbox with the same priority level and so on. Once we loop through all the * transmit mailboxes we choose the next priority level (lower) and so on * until we reach the lowest priority level on the lowest numbered mailbox * when we stop transmission until all mailboxes are transmitted and then * restart at highest numbered mailbox with highest priority. * * Two counters (head and tail) are used to track the next mailbox to transmit * and to track the echo buffer for already transmitted mailbox. The queue * is stopped when all the mailboxes are busy or when there is a priority * value roll-over happens. */ static netdev_tx_t ti_hecc_xmit(struct sk_buff *skb, struct net_device *ndev) { struct ti_hecc_priv *priv = netdev_priv(ndev); struct can_frame *cf = (struct can_frame *)skb->data; u32 mbxno, mbx_mask, data; unsigned long flags; if (can_dropped_invalid_skb(ndev, skb)) return NETDEV_TX_OK; mbxno = get_tx_head_mb(priv); mbx_mask = BIT(mbxno); spin_lock_irqsave(&priv->mbx_lock, flags); if (unlikely(hecc_read(priv, HECC_CANME) & mbx_mask)) { spin_unlock_irqrestore(&priv->mbx_lock, flags); netif_stop_queue(ndev); netdev_err(priv->ndev, "BUG: TX mbx not ready tx_head=%08X, tx_tail=%08X\n", priv->tx_head, priv->tx_tail); return NETDEV_TX_BUSY; } spin_unlock_irqrestore(&priv->mbx_lock, flags); /* Prepare mailbox for transmission */ data = cf->len | (get_tx_head_prio(priv) << 8); if (cf->can_id & CAN_RTR_FLAG) /* Remote transmission request */ data |= HECC_CANMCF_RTR; hecc_write_mbx(priv, mbxno, HECC_CANMCF, data); if (cf->can_id & CAN_EFF_FLAG) /* Extended frame format */ data = (cf->can_id & CAN_EFF_MASK) | HECC_CANMID_IDE; else /* Standard frame format */ data = (cf->can_id & CAN_SFF_MASK) << 18; hecc_write_mbx(priv, mbxno, HECC_CANMID, data); hecc_write_mbx(priv, mbxno, HECC_CANMDL, be32_to_cpu(*(__be32 *)(cf->data))); if (cf->len > 4) hecc_write_mbx(priv, mbxno, HECC_CANMDH, be32_to_cpu(*(__be32 *)(cf->data + 4))); else *(u32 *)(cf->data + 4) = 0; can_put_echo_skb(skb, ndev, mbxno, 0); spin_lock_irqsave(&priv->mbx_lock, flags); --priv->tx_head; if ((hecc_read(priv, HECC_CANME) & BIT(get_tx_head_mb(priv))) || (priv->tx_head & HECC_TX_MASK) == HECC_TX_MASK) { netif_stop_queue(ndev); } hecc_set_bit(priv, HECC_CANME, mbx_mask); spin_unlock_irqrestore(&priv->mbx_lock, flags); hecc_write(priv, HECC_CANTRS, mbx_mask); return NETDEV_TX_OK; } static inline struct ti_hecc_priv *rx_offload_to_priv(struct can_rx_offload *offload) { return container_of(offload, struct ti_hecc_priv, offload); } static struct sk_buff *ti_hecc_mailbox_read(struct can_rx_offload *offload, unsigned int mbxno, u32 *timestamp, bool drop) { struct ti_hecc_priv *priv = rx_offload_to_priv(offload); struct sk_buff *skb; struct can_frame *cf; u32 data, mbx_mask; mbx_mask = BIT(mbxno); if (unlikely(drop)) { skb = ERR_PTR(-ENOBUFS); goto mark_as_read; } skb = alloc_can_skb(offload->dev, &cf); if (unlikely(!skb)) { skb = ERR_PTR(-ENOMEM); goto mark_as_read; } data = hecc_read_mbx(priv, mbxno, HECC_CANMID); if (data & HECC_CANMID_IDE) cf->can_id = (data & CAN_EFF_MASK) | CAN_EFF_FLAG; else cf->can_id = (data >> 18) & CAN_SFF_MASK; data = hecc_read_mbx(priv, mbxno, HECC_CANMCF); if (data & HECC_CANMCF_RTR) cf->can_id |= CAN_RTR_FLAG; cf->len = can_cc_dlc2len(data & 0xF); data = hecc_read_mbx(priv, mbxno, HECC_CANMDL); *(__be32 *)(cf->data) = cpu_to_be32(data); if (cf->len > 4) { data = hecc_read_mbx(priv, mbxno, HECC_CANMDH); *(__be32 *)(cf->data + 4) = cpu_to_be32(data); } *timestamp = hecc_read_stamp(priv, mbxno); /* Check for FIFO overrun. * * All but the last RX mailbox have activated overwrite * protection. So skip check for overrun, if we're not * handling the last RX mailbox. * * As the overwrite protection for the last RX mailbox is * disabled, the CAN core might update while we're reading * it. This means the skb might be inconsistent. * * Return an error to let rx-offload discard this CAN frame. */ if (unlikely(mbxno == HECC_RX_LAST_MBOX && hecc_read(priv, HECC_CANRML) & mbx_mask)) skb = ERR_PTR(-ENOBUFS); mark_as_read: hecc_write(priv, HECC_CANRMP, mbx_mask); return skb; } static int ti_hecc_error(struct net_device *ndev, int int_status, int err_status) { struct ti_hecc_priv *priv = netdev_priv(ndev); struct can_frame *cf; struct sk_buff *skb; u32 timestamp; int err; if (err_status & HECC_BUS_ERROR) { /* propagate the error condition to the can stack */ skb = alloc_can_err_skb(ndev, &cf); if (!skb) { if (net_ratelimit()) netdev_err(priv->ndev, "%s: alloc_can_err_skb() failed\n", __func__); return -ENOMEM; } ++priv->can.can_stats.bus_error; cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_PROT; if (err_status & HECC_CANES_FE) cf->data[2] |= CAN_ERR_PROT_FORM; if (err_status & HECC_CANES_BE) cf->data[2] |= CAN_ERR_PROT_BIT; if (err_status & HECC_CANES_SE) cf->data[2] |= CAN_ERR_PROT_STUFF; if (err_status & HECC_CANES_CRCE) cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ; if (err_status & HECC_CANES_ACKE) cf->data[3] = CAN_ERR_PROT_LOC_ACK; timestamp = hecc_read(priv, HECC_CANLNT); err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp); if (err) ndev->stats.rx_fifo_errors++; } hecc_write(priv, HECC_CANES, HECC_CANES_FLAGS); return 0; } static void ti_hecc_change_state(struct net_device *ndev, enum can_state rx_state, enum can_state tx_state) { struct ti_hecc_priv *priv = netdev_priv(ndev); struct can_frame *cf; struct sk_buff *skb; u32 timestamp; int err; skb = alloc_can_err_skb(priv->ndev, &cf); if (unlikely(!skb)) { priv->can.state = max(tx_state, rx_state); return; } can_change_state(priv->ndev, cf, tx_state, rx_state); if (max(tx_state, rx_state) != CAN_STATE_BUS_OFF) { cf->data[6] = hecc_read(priv, HECC_CANTEC); cf->data[7] = hecc_read(priv, HECC_CANREC); } timestamp = hecc_read(priv, HECC_CANLNT); err = can_rx_offload_queue_sorted(&priv->offload, skb, timestamp); if (err) ndev->stats.rx_fifo_errors++; } static irqreturn_t ti_hecc_interrupt(int irq, void *dev_id) { struct net_device *ndev = (struct net_device *)dev_id; struct ti_hecc_priv *priv = netdev_priv(ndev); struct net_device_stats *stats = &ndev->stats; u32 mbxno, mbx_mask, int_status, err_status, stamp; unsigned long flags, rx_pending; u32 handled = 0; int_status = hecc_read(priv, priv->use_hecc1int ? HECC_CANGIF1 : HECC_CANGIF0); if (!int_status) return IRQ_NONE; err_status = hecc_read(priv, HECC_CANES); if (unlikely(err_status & HECC_CANES_FLAGS)) ti_hecc_error(ndev, int_status, err_status); if (unlikely(int_status & HECC_CANGIM_DEF_MASK)) { enum can_state rx_state, tx_state; u32 rec = hecc_read(priv, HECC_CANREC); u32 tec = hecc_read(priv, HECC_CANTEC); if (int_status & HECC_CANGIF_WLIF) { handled |= HECC_CANGIF_WLIF; rx_state = rec >= tec ? CAN_STATE_ERROR_WARNING : 0; tx_state = rec <= tec ? CAN_STATE_ERROR_WARNING : 0; netdev_dbg(priv->ndev, "Error Warning interrupt\n"); ti_hecc_change_state(ndev, rx_state, tx_state); } if (int_status & HECC_CANGIF_EPIF) { handled |= HECC_CANGIF_EPIF; rx_state = rec >= tec ? CAN_STATE_ERROR_PASSIVE : 0; tx_state = rec <= tec ? CAN_STATE_ERROR_PASSIVE : 0; netdev_dbg(priv->ndev, "Error passive interrupt\n"); ti_hecc_change_state(ndev, rx_state, tx_state); } if (int_status & HECC_CANGIF_BOIF) { handled |= HECC_CANGIF_BOIF; rx_state = CAN_STATE_BUS_OFF; tx_state = CAN_STATE_BUS_OFF; netdev_dbg(priv->ndev, "Bus off interrupt\n"); /* Disable all interrupts */ hecc_write(priv, HECC_CANGIM, 0); can_bus_off(ndev); ti_hecc_change_state(ndev, rx_state, tx_state); } } else if (unlikely(priv->can.state != CAN_STATE_ERROR_ACTIVE)) { enum can_state new_state, tx_state, rx_state; u32 rec = hecc_read(priv, HECC_CANREC); u32 tec = hecc_read(priv, HECC_CANTEC); if (rec >= 128 || tec >= 128) new_state = CAN_STATE_ERROR_PASSIVE; else if (rec >= 96 || tec >= 96) new_state = CAN_STATE_ERROR_WARNING; else new_state = CAN_STATE_ERROR_ACTIVE; if (new_state < priv->can.state) { rx_state = rec >= tec ? new_state : 0; tx_state = rec <= tec ? new_state : 0; ti_hecc_change_state(ndev, rx_state, tx_state); } } if (int_status & HECC_CANGIF_GMIF) { while (priv->tx_tail - priv->tx_head > 0) { mbxno = get_tx_tail_mb(priv); mbx_mask = BIT(mbxno); if (!(mbx_mask & hecc_read(priv, HECC_CANTA))) break; hecc_write(priv, HECC_CANTA, mbx_mask); spin_lock_irqsave(&priv->mbx_lock, flags); hecc_clear_bit(priv, HECC_CANME, mbx_mask); spin_unlock_irqrestore(&priv->mbx_lock, flags); stamp = hecc_read_stamp(priv, mbxno); stats->tx_bytes += can_rx_offload_get_echo_skb(&priv->offload, mbxno, stamp, NULL); stats->tx_packets++; can_led_event(ndev, CAN_LED_EVENT_TX); --priv->tx_tail; } /* restart queue if wrap-up or if queue stalled on last pkt */ if ((priv->tx_head == priv->tx_tail && ((priv->tx_head & HECC_TX_MASK) != HECC_TX_MASK)) || (((priv->tx_tail & HECC_TX_MASK) == HECC_TX_MASK) && ((priv->tx_head & HECC_TX_MASK) == HECC_TX_MASK))) netif_wake_queue(ndev); /* offload RX mailboxes and let NAPI deliver them */ while ((rx_pending = hecc_read(priv, HECC_CANRMP))) { can_rx_offload_irq_offload_timestamp(&priv->offload, rx_pending); } } /* clear all interrupt conditions - read back to avoid spurious ints */ if (priv->use_hecc1int) { hecc_write(priv, HECC_CANGIF1, handled); int_status = hecc_read(priv, HECC_CANGIF1); } else { hecc_write(priv, HECC_CANGIF0, handled); int_status = hecc_read(priv, HECC_CANGIF0); } return IRQ_HANDLED; } static int ti_hecc_open(struct net_device *ndev) { struct ti_hecc_priv *priv = netdev_priv(ndev); int err; err = request_irq(ndev->irq, ti_hecc_interrupt, IRQF_SHARED, ndev->name, ndev); if (err) { netdev_err(ndev, "error requesting interrupt\n"); return err; } ti_hecc_transceiver_switch(priv, 1); /* Open common can device */ err = open_candev(ndev); if (err) { netdev_err(ndev, "open_candev() failed %d\n", err); ti_hecc_transceiver_switch(priv, 0); free_irq(ndev->irq, ndev); return err; } can_led_event(ndev, CAN_LED_EVENT_OPEN); ti_hecc_start(ndev); can_rx_offload_enable(&priv->offload); netif_start_queue(ndev); return 0; } static int ti_hecc_close(struct net_device *ndev) { struct ti_hecc_priv *priv = netdev_priv(ndev); netif_stop_queue(ndev); can_rx_offload_disable(&priv->offload); ti_hecc_stop(ndev); free_irq(ndev->irq, ndev); close_candev(ndev); ti_hecc_transceiver_switch(priv, 0); can_led_event(ndev, CAN_LED_EVENT_STOP); return 0; } static const struct net_device_ops ti_hecc_netdev_ops = { .ndo_open = ti_hecc_open, .ndo_stop = ti_hecc_close, .ndo_start_xmit = ti_hecc_xmit, .ndo_change_mtu = can_change_mtu, }; static const struct of_device_id ti_hecc_dt_ids[] = { { .compatible = "ti,am3517-hecc", }, { } }; MODULE_DEVICE_TABLE(of, ti_hecc_dt_ids); static int ti_hecc_probe(struct platform_device *pdev) { struct net_device *ndev = (struct net_device *)0; struct ti_hecc_priv *priv; struct device_node *np = pdev->dev.of_node; struct resource *irq; struct regulator *reg_xceiver; int err = -ENODEV; if (!IS_ENABLED(CONFIG_OF) || !np) return -EINVAL; reg_xceiver = devm_regulator_get(&pdev->dev, "xceiver"); if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER) return -EPROBE_DEFER; else if (IS_ERR(reg_xceiver)) reg_xceiver = NULL; ndev = alloc_candev(sizeof(struct ti_hecc_priv), HECC_MAX_TX_MBOX); if (!ndev) { dev_err(&pdev->dev, "alloc_candev failed\n"); return -ENOMEM; } priv = netdev_priv(ndev); /* handle hecc memory */ priv->base = devm_platform_ioremap_resource_byname(pdev, "hecc"); if (IS_ERR(priv->base)) { dev_err(&pdev->dev, "hecc ioremap failed\n"); err = PTR_ERR(priv->base); goto probe_exit_candev; } /* handle hecc-ram memory */ priv->hecc_ram = devm_platform_ioremap_resource_byname(pdev, "hecc-ram"); if (IS_ERR(priv->hecc_ram)) { dev_err(&pdev->dev, "hecc-ram ioremap failed\n"); err = PTR_ERR(priv->hecc_ram); goto probe_exit_candev; } /* handle mbx memory */ priv->mbx = devm_platform_ioremap_resource_byname(pdev, "mbx"); if (IS_ERR(priv->mbx)) { dev_err(&pdev->dev, "mbx ioremap failed\n"); err = PTR_ERR(priv->mbx); goto probe_exit_candev; } irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); if (!irq) { dev_err(&pdev->dev, "No irq resource\n"); goto probe_exit_candev; } priv->ndev = ndev; priv->reg_xceiver = reg_xceiver; priv->use_hecc1int = of_property_read_bool(np, "ti,use-hecc1int"); priv->can.bittiming_const = &ti_hecc_bittiming_const; priv->can.do_set_mode = ti_hecc_do_set_mode; priv->can.do_get_berr_counter = ti_hecc_get_berr_counter; priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES; spin_lock_init(&priv->mbx_lock); ndev->irq = irq->start; ndev->flags |= IFF_ECHO; platform_set_drvdata(pdev, ndev); SET_NETDEV_DEV(ndev, &pdev->dev); ndev->netdev_ops = &ti_hecc_netdev_ops; priv->clk = clk_get(&pdev->dev, "hecc_ck"); if (IS_ERR(priv->clk)) { dev_err(&pdev->dev, "No clock available\n"); err = PTR_ERR(priv->clk); priv->clk = NULL; goto probe_exit_candev; } priv->can.clock.freq = clk_get_rate(priv->clk); err = clk_prepare_enable(priv->clk); if (err) { dev_err(&pdev->dev, "clk_prepare_enable() failed\n"); goto probe_exit_release_clk; } priv->offload.mailbox_read = ti_hecc_mailbox_read; priv->offload.mb_first = HECC_RX_FIRST_MBOX; priv->offload.mb_last = HECC_RX_LAST_MBOX; err = can_rx_offload_add_timestamp(ndev, &priv->offload); if (err) { dev_err(&pdev->dev, "can_rx_offload_add_timestamp() failed\n"); goto probe_exit_disable_clk; } err = register_candev(ndev); if (err) { dev_err(&pdev->dev, "register_candev() failed\n"); goto probe_exit_offload; } devm_can_led_init(ndev); dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%u)\n", priv->base, (u32)ndev->irq); return 0; probe_exit_offload: can_rx_offload_del(&priv->offload); probe_exit_disable_clk: clk_disable_unprepare(priv->clk); probe_exit_release_clk: clk_put(priv->clk); probe_exit_candev: free_candev(ndev); return err; } static int ti_hecc_remove(struct platform_device *pdev) { struct net_device *ndev = platform_get_drvdata(pdev); struct ti_hecc_priv *priv = netdev_priv(ndev); unregister_candev(ndev); clk_disable_unprepare(priv->clk); clk_put(priv->clk); can_rx_offload_del(&priv->offload); free_candev(ndev); return 0; } #ifdef CONFIG_PM static int ti_hecc_suspend(struct platform_device *pdev, pm_message_t state) { struct net_device *dev = platform_get_drvdata(pdev); struct ti_hecc_priv *priv = netdev_priv(dev); if (netif_running(dev)) { netif_stop_queue(dev); netif_device_detach(dev); } hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_PDR); priv->can.state = CAN_STATE_SLEEPING; clk_disable_unprepare(priv->clk); return 0; } static int ti_hecc_resume(struct platform_device *pdev) { struct net_device *dev = platform_get_drvdata(pdev); struct ti_hecc_priv *priv = netdev_priv(dev); int err; err = clk_prepare_enable(priv->clk); if (err) return err; hecc_clear_bit(priv, HECC_CANMC, HECC_CANMC_PDR); priv->can.state = CAN_STATE_ERROR_ACTIVE; if (netif_running(dev)) { netif_device_attach(dev); netif_start_queue(dev); } return 0; } #else #define ti_hecc_suspend NULL #define ti_hecc_resume NULL #endif /* TI HECC netdevice driver: platform driver structure */ static struct platform_driver ti_hecc_driver = { .driver = { .name = DRV_NAME, .of_match_table = ti_hecc_dt_ids, }, .probe = ti_hecc_probe, .remove = ti_hecc_remove, .suspend = ti_hecc_suspend, .resume = ti_hecc_resume, }; module_platform_driver(ti_hecc_driver); MODULE_AUTHOR("Anant Gole "); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION(DRV_DESC); MODULE_ALIAS("platform:" DRV_NAME);